Mounting for pilot light



April 1966 N. HOUBOLT 3,246,320

MOUNTING FOR PILOT LIGHT Filed Feb. 24, 1964 50 It I 5z 2 2 I 45 w I M l V H 4 I i 4.

'38 I IIII' Z6 1 IH, 1,8

I i --54 z;

gzi a T aw INVENTOR.

NEAL HOUBOLT United States Patent Ofiice 3,246,320

Patented Apr. 12, 1966 3,245,320 MOUNTENG FGR PILOT LIGHT Neal Houbolt, Juliet, llL, assignor to .lesnco Enginee ing (10., .loiiet, iii, a corporation of Illinois Filed Feb. 24, 1964, Ser. No. 346,896 8 Claims. (Cl. 340-4381) This invention relates to pilot lights used as indicators on various household appliances and certain industrial equipment, and more particularly to a mounting construction by means of which such a pilot light may be inserted into a mounting plate to snap into position so that it is not removable from the front side of the plate but is readily removable from the rear of the plate.

Many kinds of electrically operated household and industrial devices are equipped with one or more pilot lights which serve to notify the user of some condition prevailing in the device. For instance, many electric coffee makers have a pilot light which informs the housewife that the coffee is ready to serve. Another common use of the pilot light in both household and industrial devices is to inform the user that the device is on rather than off. There are many other similar uses of such pilot lights.

Pilot lights of this character are mounted in standardsized holes in mounting panels which vary in thickness from .020 inch to approximately .065 inch. In order to hide the hole in the mounting panel the pilot light'is provided, at its lens end, with a flange of greater diameter than the diameter of the hole. This flange is sometimes covered with a decorative ring or bezel. Since the outer diameter of the lens end of the pilot light is greater than the diameter of the hole in the mounting panel, the pilot light must be inserted from the face of the panel rather than from its rear.

A desirable characteristic of these pilot lights is that they be capable of being inserted from the face of the mounting panel and snap into final position without the use of some extra fastening means which must be assembled from the rear of the panel. It is also desirable that the mounted pilot light be tamperproof, i.e. that it not be removable from the face of the mounting panel alone. Finally, it is desirable that the pilot light be readily removable from the back of the mounting panel. My pilot light mounting construction has all of these desirable characteristics while conforming to the other requirements of such pilot lights.

An earlier form of pilot light has a cylindrical housing in which the electrical components are situated. It can be inserted in a hole in a mounting panel from the front f the panel. However, to hold it in position it is necessary to assemble a fastening device from the rear of the panel, as an additional step. Such a fastening device as the widely used Speed Nut is normally employed with this pilot light. ing. However, it is almost impossible to remove the Speed Nut from the cylindrical housing in case it should become necessary to remove the pilot light for replacement.

Other pilot lights are known in which the cylindrical housing is deformed in going through the hole in the panel when the light is inserted. A tight fit is obtained by reason of the deformation. These include housings having axial slots to permit such deformation. Others have small projections on the sides of the cylinders near the lens end, which projections engage the rear of the mounting panel. Another closely related earlier construction involves the use of a decorative bezel around the lens of the pilot light, the bezel having a number of spring fingers which extend axially down the cylindrical housing, which fingers engage the rear of the mounting panel to hold the light in the desired position. However,

This gives a tight, tamperproof mountnone of these pilot lights (whether deformation takes place in the housing or in fingers on the bezel) has the characteristic of a tamperproof mountingal1 of them can be readily removed from the face side of the mounting panel with the use of a small knife or screwdriver.

Another earlier pilot light is insertable from the front of the mounting panel and snaps into its permanent position without the use of any secondary securing means which must be assembled from the rear of the mounting panel. It is secured by arms which radiate from the housing and which are deformed during insertion. It is not possible to remove this pilot light from the front of the panel alone. However, it is almost impossible to re- .move this light from the panel after obtaining access to the rear of the panel, because of the shape and stiffness of the arms employed to hold the light in the mounted position.

It is therefore an object of this invention to provide locking means associated with the housing of a pilot light wherein the pilot light may be inserted from the face of the mounting plate and the locking means will effectively prevent removal from the face of the plate alone, while permitting easy removal of the pilot light through access to the rear of the mounting plate.

Another object is to provide locking means associated with the housing of a pilot light whereby the pilot light may be installed with a single motion and elfectively prevented from withdrawal from the mounting plate unless access is had to the rear of the mounting plate, from which position withdrawal is very easy.

Another object is to provide locking means associated with the housing of a pilot light which locking means is usable with a wide range of thicknesses of the mounting plate or panel, automatically effectively locking the pilot light in mounting plates of varying thicknesses and in such manner that it is tightly mounted regardless of the thickness of the plate or panel.

Another object is to provide locking means associated with the housing of a pilot light wherein the structure of the locking means also provides an electric-insulating barrier within the pilot light.

Further objects and advantages of my invention will be apparent from the following specification together with the accompanying drawings, in which,

FIG. 1 is a view in elevation showing the pilot light mounted in a mounting panel;

FIG. 2 is a view of the pilot light, partially in section, showing one of the locking arms;

FIG. 3 is an exploded view, with some parts omitted, showing the pilot light housing and the locking insert prior to assembly;

FIG. 4 is a view in elevation of the housing alone, showing the positions of the apertures therein;

FIG. 5 is an enlarged view in partial cross-section showing the locking means in position in the housing;

FIG. 5a is a view similar to a portion of FIG. 5, but showing a panel or mounting plate of greater thickness.

FIG. 6 is a view similar to FIG. 5 but taken on a plane perpendicular to the plane of FIG. 5, and

PEG. 7 is a view on the line 77 of FIG. 5.

Referring to the drawings, the pilot light 10 is shown in FIG. 1 positioned in a mounting panel 12 through a suitable aperture. The cylindrical housing 14 is of a slightly smaller diameter than the aperture in the panel 12.. The lens 16 is of a larger diameter than the diameter of the aperture 13 in the panel 12, and may be fitted with a decorative ring or bezel 18 (FIG. 5). As shown, the lens 16 is molded as a piece of the housing 14. However, the lens 16 may be separately molded and suitably attached to the housing 14, and may be or" any desirable shape, such as flat, slightly domed, hemispherical, or cylindrical. The shape of the lens 16 and its method of attachment to the housing 14 have nothing to do with this invention, so long as an annular shoulder such as at 20 is provided to act as a stop against the face of the mounting panel 12. i

As shown in FIGS. 4, and 7, a pair of diametrically opposed slots 22 are formed in the housing 14 near the lens 16. A pair of diametrically opposed apertures 24 are located toward the base of the unit, with respect to the lens in. The housing 14 may be molded from one of the resilient plastic materials, such as nylon.

The insert, identified generally by the reference character 25 in FIG. 3, may also be molded from one of the resilient plastic materials such as nylon, or others having comparable insulating characteristics. The insert 25 is formed with a cylindrical base 26 adapted to fit inside the housing 14, and with a radially extending flange 28 which fits against the base of the housing 14 and limits the movement of the insert 25 into the cavity in the housing 14. An external central Web 30 extends below the base 25 and the flange 28, and between the tab terminals 32 where it acts as an insulating electrical barrier. As shown, the pilot light is provided with male tab terminals for connection with mating terminals to supply current to the pilot light. The structure may also be supplied with standard wire leads suitably connected to its electrical components in place of the tab terminals 32.

The insert 25 is also formed with an internal central web 34 which functions as an insulating electrical barrier within the housing 14. The webs 39 and 34 are preferably in the same plane and extend radially for substantially the full diameter of the cavity in the housing 14.- The external web 30 may be slightly tapered, as shown especially in FIG. 5.

Locking pegs 36 extend radially from the web 34 for engagement with the apertures 24 in the wall or" the housing 14. In assembling the insert 25 with the housing 14, the wall of the housing 14 will distort sufficiently to permit the pegs 36 to be forced into position in the apertures 24.

The resilient locking legs 38 extend from the web 34 toward the lens 16 and terminate in the angularly disposed locking feet 40. The feet 48 are provided with an upper surface 42 which diverges outwardly with respect to the surface 26) to accommodate mounting panels of various thicknesses. In those cases where the pilot light It) is used with a relatively thin mounting panel, the feet 40 will extend a substantial distance out of the slots 22, and the extreme upper end (as seen in FIG. 5) of the surface 42 will engage the rear surface of the mounting panel 12. Where the pilot light is used with a relatively thick mounting panel, the feet 4t) extend a lesser distance (see FIG. 5a) through the slots 22, and surface 42, nearer its outer radial extremity, will engage the rear surface of the mounting panel 12. The angular disposition of the surface 42 with respect to the surface 20, together with the resilience of the locking legs 38, will provide a tight, tamperproof mounting on panels of various thicknesses.

The face 44 on each of the resilient locking legs 38 acts as a cam during insertion of the pilot light it) into an aperture 13 in a mounting panel 12 as shown dotted in FIG. 5a. The engagement of the faces 44 with the inner edge of the aperture 13 forces the legs 38 radially inward to permit the surface 42 to snap under the rear surface of the mounting panel 12, to provide a tamperproof mounting. The faces 44 have an additional function in connection with the removal of the pilot light from the mounting panel. If removal is desired, a removal cylinder, 54 shown dotted in FIG. 5, having an internal diameterequal to the diameter of the aperture in the panel, is slipped over the bottom of the housing 14. The removal cylinder is then forced up against the mounting panel. When the upper edge of the removal cylinder engages the faces 44, the locking legs 38 and the surfaces 4-2 will be c-ammed out of the locking position, and the pilot light 19 may be withdrawn from the aperture in the mounting panel 12.

A neon bulb 46 is mounted in the central cavity of the housing 14 and is supported by the electrical conductors which also supply it with current. A conductor 48 is connected directly to one of the tab connectors 32, While the conductor 50 is connected to a resistor 52, which is in turn connected to the other tab connector 32. The resistor 52 may be placed on one side of the web 34, while the bulb 46 is offset to the opposite side. This offsetting of the bulb 46 provides space for the locking legs 38 to be bent inwardly with respect to the housing 14 during installation or withdrawal of the pilot light It Having described my invention, what I claim as new and desire to protect by Letters Patent is:

1. In a pilot light of the character disclosed adapted to be mounted in an opening of a panel and to project inwardly therefrom, a cylindrical housing having a flange around its outer end overlapping the edge of such an opening, a pilot light mounting means in said cylinder, a pair of opposed resilient arms carried by said pilot light mounting means in said cylinder and projecting toward said flange, said arms having cam-like terminal ends, the diametrically opposed extremities of which are normally farther apart than the internal diameter of said cylindrical housing, said cylindrical housing having openings through which said cam-like terminal ends extend, said terminal ends being adapted to assume positions adjacent said flange in the mounted position of said pilot light mounting means in said cylindrical housing, the resiliency of said arms tending to spread them apart, said cam-like ends coacting with the inner edge of the panel opening when so spread to mount said cylindrical housing relative to said panel.

2. A pilot light according to claim 1 wherein said camlike terminal ends of said arms have cam surfaces diverging outwardly with respect to said flange to so coact with the inner edge of the panel opening as to draw said flange into tight engagement with the outer surface of said panel.

3. A pilot light according to claim 1 wherein said cam-like terminal ends of said arms have first cam surfaces diverting outwardly With respect to said flange to coact with the inner edge of the panel opening and second cam surfaces converging outwardly with respect to said flange with which a removable cylinder telescoped over said cylindrical housing is adapted to coact to contact said arms so that said cylindrical housing may be removed from the panel opening.

4. A pilot light in accordance with claim 1 wherein said pilot light mounting means has projections adjacent the inner end of said cylindrical housing entering perforations in the housing to coact with said cam-like terminal ends of said arms to mount said pilot light mounting means with respect to said cylindrical housing.

5. A pilot light in accordance with claim 4 wherein said pilot light mounting means also has a closure element for the inner end of said cylindrical housing.

6. In a pilot light for mounting in an aperture in a panel and having a housing with an abutment flange adjacent its lens end, said flange being adapted to engage the front surface of a mounting panel, said housing having an aperture in its side wall adjacent said flange, the provision of a resilient locking member mounted on means located within said housing and having a terminal end normally extending outward through the aperture in said housing for engagement with the rear surface of a mounting panel, said resilient locking member being movable toward the inside of said housing for insertion and removal of said pilot light into and out of an aperture in a mounting panel.

-7. In a pilot light for mounting in an aperture in a panel and having a housing with an abutment flange adjacent its lens end, said flange being adapted to engage the front surface of a mounting panel, said housing having a plurality of apertures in its side wall adjacent said flange, the provision of a plurality of resilient locking members mounted on means located within said housing and having a terminal end normally extending outward through the apertures in said housing for engagement with the rear surface of a mounting panel, said resilient locking members being movable toward the inside of said housing for the insertion and removal of said pilot light into and out of an aperture in a mounting panel.

8. In a pilot light for mounting in an aperture in a panel nad having a housing with an abutment flange adjacent its lens end, said flange being adapted to engage the front surface of a mounting panel, said housing having a plurality of apertures in its side wall adjacent said flange, the provision of pilot light mounting means in said housing comprising a base portion, -a pair of electrical connectors extending through said base portion, an insulating web extending from said base portion between said connectors, and a pair of opposed resilient arms extending inside said housing from said base toward said flange and through said apertures outward of the side 6 wall of the housing, the diametrically opposed extremities of said arms being normally farther apart than the internal diameter of said housing and being adapted to move outwardly into engagement with one wall of a panel whereby said flange is held against the opposite Wall of the panel.

References Cited by the Examiner UNITED STATES PATENTS NEIL C. READ, Primary Examiner. A I. KASPER, Assistant Examiner, 

1. IN A PILOT LIGHT OF THE CHARACTER DISCLOSED ADAPTED TO BE MOUNTED IN AN OPENING OF A PANEL AND TO PROJECT INWARDLY THEREFROM, A CYLINDRICAL HOUSING HAVING A FLANGE AROUND ITS OUTER END OVERLAPPING THE EDGE OF SUCH AN OPENING, A PILOT LIGHT MOUNTING MEANS IN SAID CYLINDER, A PAIR OF OPPOSED RESILIENT ARMS CARRIED BY SAID PILOT LIGHT MOUNTING MEANS IN SAID CYLINDER AND PROJECTING TOWARD SAID FLANGE, SAID ARMS HAVING CAM-LIKE TERMINAL ENDS, THE DIAMETRICALLY OPPOSED EXTREMITIES OF WHICH ARE NORMALLY FARTHER APART THAN THE INTERNAL DIAMETER OF SAID CYLINDRICAL HOUSING, SAID CYLINDRICAL HOUSING HAVING OPENINGS THROUGH WHICH SAID CAM-LIKE TERMINAL ENDS EXTEND, SAID EXTERNAL ENDS BEING ADAPTED TO ASSUME POSITIONS ADJACENT SAID FLANGE IN THE MOUNTED POSITION OF SAID PILOT LIGHT MOUNTING MEANS IN SAID CYLINDRICAL HOUSING, THE RESILIENCY OF SAID ARMS TENDING TO SPREAD THEM APART, SAID CAM-LIKE ENDS COACTING WITH THE INNER EDGE OF THE PANEL OPENING WHEN SO SPREAD TO MOUNT SAID CYLINDRICAL HOUSING RELATIVE TO SAID PANEL 